Wrought iron or steel core bar



Feb. 1 1927.

HQE. RUDISILL BON 0R STEEL CORE BAR Filed June //V //////////f/// \`N\ /Q ,w n SWR @Hommj l Patented Feb. 1, 1927.

UNITED STATES Pa'rinrr oFFicE.

VROUGHT IRCINl OR STEEL-.GORE BAR.

Application filed June 3,

My* invention relates to core bars and'particularly toy core bars of the type used in the manufacture of cast iron pipe and tubular cast articles.

Heretofore core bars for cast iron pipe have been made of double eXtra strong wrought iron or steel pipe having a cast iron head mounted on one end thereof. Where such corebarslare designed for the produc- IU tion of 2 cast iron pipe, the core bar has been made of( 1 double extra strong pipe7 and in the practical' use of such'core bars considerable ditliculty is encountered inV unloading them when the molten iron, in vpouring the cast iron pipe, gains access to and passes throughy the vent holes into the core bar. The internal diameter of such core bar pipe being: approximately 1/2 makes it possibleto use only a small diameter and rela- 2G tively weak rod or ban for driving out the iron inthe core bar or unloading it, andthis has resultedin the frequent .scrapping of such core bars which entails substantial loss due to the relatively high.I costi per foot of double eXtra strong wrought pipe.

I have conceived that wrought iron or steel pipe can be more successfully used in the production of core bars if instead of a single double eXtra strong pipe two wrought metal pipes telescoped together aresubstituted to form the core bar. Thus, for a 2 core bar, I propose the use of an outer eXtra strong wrought iron or steel pipe which has an inside bore of about S diameter, and I insert within same a smaller pipe such as a- 1/2 standard pipe which has an inside diameter of 1/2 and an outside diameter of about 5/8 of an inch. snugly when assembled and are riveted to hold them in position so that the vent holes with which they are provided will register.

As a result of this arrangement when my assembled double pipe core bar requires unloading, the inner pipe can be removed, unloaded and replaced, or a new inner pipe may be substituted, in which latter event the loss by scrappage is but a fraction of the loss where double extra strong pipe is scrapped.

Moreover, the inner pipe can be readily driven out for unloading` after the rivet assembling it in the outer pipe has been cut, because a bar or rod having almost a 3A diameter can be used in the outer pipe to drive the inner pipe out.

These two pipes will fit 1926., serial No. 113,430.

I have also found that core barsV made up of" assembledL pipein the mannerabove described will not break` in straighteningas' readily as a single double eXtra strong pipe core bar. l

A further object of my invention is to provide inwardly converging tapering vent holes in the outer pipe which register with uniform diameter holes bored through the inner pipe, the registering holes providing" ample venting for the core bar.`

My invention further comprises the novel features of construction and arrangements of parts, which are hereinafter more` particularly described and pointed out the appended claims, reference being'had to the accompanying drawings which form a part ofl this specification, and in which only 'the preferred embodiment of my invention is illustrated. p

According to the drawings y Fig. 1 is a plan view of a core bar made up in accordance with my invention.

Fig. 2 is a cross-sectional view taken on theline 2-2 of Fig. 1.

Fig. 3 is a longitudinal cross-sectional view enlarged and partly broken away, taken on the line 3 3 of Fig. l.

Similar reference numerals refer to similar parts throughout the drawings.

In the embodiment of my invention illustrated, I show a core bar intended for use in the manufacture of cast iron pipe, but it will, of course, be understood that my invention contemplates the designing and arranging of .such core bar or arbor for vari# ous other analogous uses. The typical core bar selected to illustrate my invention is suited for the production of 2 cast iron pipe and I show the same as comprising an outer 1 eXtra strong wrought iron or steel pipe 1 cut to the desir-ed length and having mounted thereon a cast iron head 2 of any standard design which is made fast thereon in accordance with the established practice. Within the pipe 1 I insert a smaller pipe 3, preferably a standard l/2 wrought iron or steel pipe, which will have a diameter that will permit it to be readily inserted in the bore of the pipe 1 and secured in fixed relation thereto by means of a rivet 4. In the outer pipe 1 I provide a series of vent holes 5 which are drilled tapering `so as to converge inwardly towards the bore yof the pipe 1 and in the pipe 3 I provide a series of vent holes 6 which are drilled straight and ot even ydiameter and disposed to register with the vent holes 5.

I-Iaving assembled the core bar in the manner described in use, it Will be found that it can be more easily straightened without breaking than the .single pipe core bars and that When, due to the molten metal running through the vent holesI 5 and 6 it becomes necessary to unload the core arbor, this can be done readily by cutting the rivet A and driving the inner pipe 3 out of the pipe l. As this occursthe pipe 3 shears the necks oi the metal in the holes 5 and 6 so that the taper plugs remaining in the taper holes 5 can be readily knocked out with a hammer using a tapered steel punch Where necessary. The smaller pipe 3 When removed can be as readily unloaded as the double extra strong single pipe core bars because it will have the same internal diameter, but, when it cannot be readily unloaded, this inner pipe 3 can be scrapped and another pipe substituted With marked saving due to the fact that the standard 1/2 pipe 3 costs about 2O percent of the double eXtra strong l pipe. rIhus, my improved assembled pipe core bar Will not only provide pipe foundries with a better core bar but Will also materially reduce their operating costs because of its lower maintenance cost and replacement expense as compared to the present 'core bars.

' Though I have described With great particularity the details of the embodiment of the invention herein shown, it is not to be construed that I am limited thereto, as changes in arrangement and substitution of equivalents may be made by those skilled in the art Without departing from the invention as delined in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

l. A core bar of the character described, comprising assembled inner andl outer pipes secured together and provided with registering vent holes, and a head mounted on one end of the assembled pipes.

2. A core bar of the character described, comprising tivo assembled pipes, the outer being an eXtra strong Wrought metal pipe and the inner a standard Wrought metal pipe, means. to tasten the pipe together, and a head mounted on said outer pipe, there being registering vent lholes. through the pipes.

3. A core bar according to claim 2, in which the vent holes taper inwardly in the outer pipe and are of uniform diameter in the inner pipe.

t. A core bar according to claim 2, in

Which the means to fasten the pipes together consists of. a rivet through the end of the assembled core bar remote from the head.

In testimony whereof I, HENRY B. RonisILL, aiix my signature.l

HENRY B. RUDISILL. 

